diff --git a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go
index 7c4ab2cf612..5e0d652206e 100644
--- a/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go
+++ b/staging/src/k8s.io/kube-aggregator/pkg/apiserver/handler_proxy.go
@@ -18,7 +18,6 @@ package apiserver
 
 import (
 	"context"
-	"fmt"
 	"net/http"
 	"net/url"
 	"sync/atomic"
@@ -208,15 +207,12 @@ func (r *proxyHandler) updateAPIService(apiService *apiregistrationapi.APIServic
 		serviceNamespace: apiService.Spec.Service.Namespace,
 		serviceAvailable: apiregistrationapi.IsAPIServiceConditionTrue(apiService, apiregistrationapi.Available),
 	}
+	if r.proxyTransport != nil && r.proxyTransport.DialContext != nil {
+		newInfo.restConfig.Dial = r.proxyTransport.DialContext
+	}
 	newInfo.proxyRoundTripper, newInfo.transportBuildingError = restclient.TransportFor(newInfo.restConfig)
-	if newInfo.transportBuildingError == nil && r.proxyTransport != nil && r.proxyTransport.DialContext != nil {
-		switch transport := newInfo.proxyRoundTripper.(type) {
-		case *http.Transport:
-			transport.DialContext = r.proxyTransport.DialContext
-		default:
-			newInfo.transportBuildingError = fmt.Errorf("unable to set dialer for %s/%s as rest transport is of type %T", apiService.Spec.Service.Namespace, apiService.Spec.Service.Name, newInfo.proxyRoundTripper)
-			glog.Warning(newInfo.transportBuildingError.Error())
-		}
+	if newInfo.transportBuildingError != nil {
+		glog.Warning(newInfo.transportBuildingError.Error())
 	}
 	r.handlingInfo.Store(newInfo)
 }